Digital gas mass flow controllers

数字气体质量流量控制器

• 批准号: 359286-2008
• 负责人: Reid, Stephen
• 金额: $ 0.78万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments - Category 1 (<$150,000)
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=366058
• 关键词: Digital; gas; mass; flow; controllers

This proposal is requesting funding to purchase gas flow controllers which are instruments that allow for the precise regulation of the amount of gas (oxygen, carbon dioxide and nitrogen) that flows into an experimental set-up. These controllers are connected to tanks of compressed gases which provide the controller with an inflow of gas. The inflow of gas is regulated in terms of the pressure delivered to the controller but not in terms of the actual quantity or volume of gas. The controller is then set such that the outflow of gas from the controller is tightly and accurately regulated in terms of the volume of out-flowing gas per minute. The research that this equipment will support examines mechanisms involved in controlling breathing in amphibians. Amphibian breathing is interesting and important because, unlike humans and other mammals, amphibians do not breathe continuously. Rather, they display a discontinuous pattern of breathing called episodic breathing. This type of breathing involves the grouping of 4-8 breaths into discrete episodes separated by periods of no breathing called apneas (which can be several minutes in length). While episodic breathing is normal in amphibians, it is abnormal and pathological in humans. Humans can display this pattern of breathing during sleep either due to an obstruction of the airway (obstructive sleep apnoea) or due to abnormalities in the areas of the brain that regulate continuous breathing (central sleep apnoea). Apnoea in humans is associated with increased risk for cardiovascular disease such as heart attack or stroke. This research will examine the mechanisms within the amphibian brain that lead to the production of episodic breathing and may lead to insight into brain-related breathing disorders in humans. To do this, we experimentally manipulate neurochemical systems in various regions of the brain (by injecting various drugs) and observe how breathing changes. Since different levels of oxygen and carbon dioxide can alter breathing on their own (without manipulating brain neurochemicals) it is essential that we control the gas levels in an experiment using the gas flow controllers.

这项提案要求提供资金购买气体流动控制器，这是一种允许精确调节流入实验装置的气体(氧气、二氧化碳和氮气)数量的仪器。这些控制器与压缩气体储罐相连，压缩气体储罐为控制器提供气体流入。气体的流入是根据输送给控制器的压力来调节的，而不是根据实际的气体数量或体积来调节的。然后对控制器进行设置，以使控制器的气体流出量根据每分钟流出的气体的量被严格而准确地调节。该设备将支持的研究检查涉及控制两栖动物呼吸的机制。两栖动物的呼吸很有趣，也很重要，因为与人类和其他哺乳动物不同，两栖动物不会持续呼吸。相反，他们表现出一种不连续的呼吸模式，称为间歇性呼吸。这种类型的呼吸包括将4-8次呼吸分成几个不同的阶段，由称为呼吸暂停的无呼吸周期分隔(可能长达几分钟)。虽然间歇性呼吸在两栖动物中是正常的，但在人类中是异常的和病态的。人类可以在睡眠中表现出这种呼吸模式，要么是由于呼吸道阻塞(阻塞性睡眠呼吸暂停)，要么是由于调节持续呼吸的大脑区域异常(中枢性睡眠呼吸暂停)。人类的呼吸暂停与心脏病发作或中风等心血管疾病的风险增加有关。这项研究将研究两栖动物大脑中导致间歇性呼吸产生的机制，并可能导致对人类大脑相关呼吸障碍的洞察。为了做到这一点，我们通过实验操纵大脑不同区域的神经化学系统(通过注射各种药物)，并观察呼吸如何变化。由于不同水平的氧气和二氧化碳可以自行改变呼吸(而不需要操纵大脑神经化学物质)，因此我们必须在使用气体流量控制器的实验中控制气体水平。